From the prior art synchronizers are known, which include a synchronizer body associated to a transmission shaft. On the synchronizer body a thrust piece typically is shiftably arranged, which during a shifting operation is moved by a sliding sleeve such that it activates a synchronizer ring. The synchronizer ring in turn cooperates with a transmission gear, whereby the rotational speeds of the synchronizer body and of the corresponding transmission gear can be synchronized. After synchronization of the rotational speeds, the sliding sleeve is shifted further so that a torque can be transmitted from the synchronizer body arranged on the transmission shaft to the corresponding transmission gear.
It was found that on meshing of the sliding sleeve on the transmission gear, the synchronizer ring continues to be axially loaded by the thrust piece such that a friction moment is obtained, which must be overcome on meshing. The cause for the further axial loading of the synchronizer ring by the thrust piece chiefly is the friction between the thrust piece and the synchronizer body on which the thrust piece is arranged. Due to the friction between the thrust piece and the synchronizer body an axial return movement of the thrust piece is prevented. The disadvantage consists in that when engaging a gear, an increased expenditure of force is necessary in order to overcome the frictional force generated by the synchronizer ring via the thrust piece. This problem occurs in particular when a vehicle is stationary.
It therefore is the object of the invention to create a synchronizer which provides for smoothly engaging the gear.